Waste compactors

ABSTRACT

A waste compactor for compacting waste in a container comprises a ram which reciprocates into and out of the container to compress the waste. The ram is preferably box-like and has a bottom opening which is normally closed by doors or flaps. Waste material can be fed into the compactor at a level above the opening and, when the doors are opened, preferably automatically during the ram stroke, the waste passes through the opening to the container, the doors being closed before the ram compresses the waste material.

Nov. 4, 1975 100/229 A IOU/290 3145,647 8/1964Dinkov........................... 3,537,390 11/1970 Hinkel......

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England Primary ExaminerRobert W. Jenkins [73] Assignee: R. G. Dixon &Company Limited, Attorney, Agent, or Firm-Finnegan, Henderson,

Wembley, England Farabow & Garrett Jan. 9, 1974 [21] Appl. No.: 431,850

[22] Filed:

ABSTRACT A waste compactor for compacting waste in a container comprisesa ram which reciprocates into and out of the container to compress thewaste. The ram is [52] US. 100/229 A; 100/256; IOU/290;

preferably box-like and has a bottom opening which is [51] Int. rm ly loe y oors or flaps. Waste material can [58] Field of Search 100/229 A,295, 256, 215, be fed into the compactor at a level above the openingand, when the doors are opened, preferably automatically during the ramstroke, the waste passes through the opening to the container, the doorsbeing closed before the ram compresses the waste material.

References Cited UNITED STATES PATENTS 2,421,465 100/215 9 Claims, 11Drawing Figures .r- Lrlillilill! idb 2 il. a HH? lllllllllllll l t I I 1I i l I I i l l .rr

US. Patent Nov.4, 1975 Sheetlof7 3,916,782

US. Patent Nov. 4, 1975 Sheet2 0f7 3,916,782

Sheet 3 of 7 U.S. Patent N0v,.4, 1975 lll llk

US. Patent Nov.4, 1975 Sheet5of7 3,916,782

US. Patent Nov. 4, 1975 Sheet 6 of7 3,916,782

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WASTE COMPACTORS This invention relates to waste compactors of the formcomprising a ram and a drive arrangement operable to reciprocate the raminto and out ofa container to compress waste material therein.

In known compactors of this general form the ram is moved upwardly outof the container when it is desired to insert waste material and thewaste material is fed into the container through an opening below thelevel of the raised ram. The opening is normally closed by a door whichwhen opened cuts out all operations of the waste compactor, but there isa possibility that, due to a fault, the ram could move downwardly whilewaste is being inserted in the container and crush the hand or arm ofthe person inserting the waste. Furthermore, while the ram is raised toinsert waste material, air can circulate around the waste and out of theopening carrying with it any unpleasant odours.

The present invention overcomes these disadvantages of the knowncompactors and provides a waste compactor in which waste material can befed into the container through an opening above the level of the ram.

In accordance with the invention there is provided a waste compactorcomprising a ram and a drive arrangement operable to reciprocate the raminto and out of a container to compress waste material therein,characterized in that the ram has a bottom opening to permit wastematerial inserted in the compactor at a level above the opening to passthrough the ram into the container, and that the ram has a closureassembly which closes the opening before the ram compresses the wastematerial in the container.

Preferably, the closure assembly comprises one or more doors or flapswhich are opened automatically towards the end of the upward stroke ofthe ram by respective door-operating mechanisms.

In one form of waste compactor described in more detail below, the cycleof the ram is controlled by ramoperated micro-switches located in ornear the working area of the ram. While this is acceptable for somewaste compactors, in an alternative form of compactor the micro-switchesand their electrical connections are remote from the working area of theram. In this alternative form, the micro-switches are easier to reachfor repair or service and the problems of insulation are not so greatsince the micro-switches do not come into contact with moisture from thewaste material.

In the alternative form of the compactor according to the presentinvention, a ram position indicating device is mounted remote from theram and comprises a further .feed screw drivingly coupled to the drivefeed screws and carrying a nut member held against rotation, movementsof the nut member along the further feed screw representing on a reducedscale movements of the ram along the drive feed screws. Themicro-switches are mounted for engagement by the nut member to controlthe motor. Thus, the micro-switches and their electrical connections areremote from the working area of the ram.

One form of waste compactor in accordance with the invention will now bedescribed, by way of example, with reference to the accompanyingdrawings, in which:

FIG. 1 is a perspective view of the waste compactor,

FIG. 2 is a side view of the waste compactor with the housing removed,and showing a ram in its retracted position,

FIG. 3 is a plan view of the waste compactor with the housing removed,

FIG. 4 is an enlarged view ofa mechanism for operating flaps or doors ofthe ram,

FIG. 5 is an enlarged part-sectional view of a load sensing device ofthe waste compactor, and

FIG. 6 is an enlarged view of part of the waste compactor and a wastecontainer supported therein,

FIG. 7 is a sectional view of part of the ram showing part of a modifiedform of door operating mechanisms,

FIG. 8 is a section taken along line B-B of FIG. 7,

FIG. 9 is a part-sectional view of a further modification showing a ramposition indicating device,

FIG. 10 is a plan view of the device of FIG. 9, and

FIG. 11 is an enlarged view of a modified door of the waste compactor.

The waste compactor comprises a frame for a sheet metal housing 1 whichhouses a ram 2 and a removable container 3. The ram 2 is a box-likestructure and is supported by three generally equiangularly spaced drivefeed screws 4 each of which is rotatably mounted in thrust bearings 5and carries ram frame members 8 comprising a captive nut 6. A reversiblemotor 9 has a pulley 11 connected to its drive shaft and drivinglycoupled by an endless toothed drive belt 13 to a pully 12 fast with oneof the screws 4. The drive is transmitted to the other screws 4 by afurther endless toothed belt 14 passing around three pulleys 15 mountedon the respective screws 4.

A hinged door 16 can be opened for the insertion of waste into thecompactor above the ram 2 so that there is no possibility of the ramcrushing the fingers or arm of the user when waste is inserted.

Flaps or doors 17 are provided at the bottom of the ram 2 to allow thewaste to pass through into the container 3. The doors 17 are arranged toopen automatically as the ram 2 approaches the end of its upward strokeby respective door operating mechanisms 18 shown clearly in FIG. 4, eachof which comprises a rod 19 passing through apertured guide members 20attached to the frame of the ram 2 and screw threadedly connected at itslower end to a lug 21 which is pivotally connected to a lever 22. Eachdoor is pivotable about a hinge 23 along one edge, the lever v22 beingpivotally connected to the door adjacent said edge and centrallythereof. A compression coil spring 24surrounds the rod and is arrangedto act between the lower guide member 20 and an abutment member 25connected, for example by a pin 26, to the rod 19.

As the ram approaches the end of its upward stroke, each rod 19 abuts afixed frame member 27 of the compactor and moves downwardly, relative tothe ram 2, against the action of the spring 24 to the position shown inchain lines in FIG. 4. This movement causes corresponding movement ofeach lever 22 to open the doors 17.

When the ram starts its downward stroke the force of springs 24 keepsthe rods 19 in abutting engagement with the frame members 27, and therods therefore move upwardly relative to the ram 2 and the doors close.

To operate the compactor the electrical supply is switched on and isindicated by an indicating lamp 10 and a start button 28 on the housingis actuated to start 3 the motor 9 to bring the ram 2 to its startingposition, i.e. to the end of its downward stroke.

The electrical circuitry forms no part of the present invention and neednot be described in this specification.

Waste can now be inserted into the compactor through the waste door 16which operates a microswitch 29 as it opens to cut out all mechanicalfunctions and prevent the ram moving while there is a possibility of ahand being inserted through the opening. The waste falls into the ram 2through a guide chute 30 and the door 16 is closed to actuate themicro-switch 29 and operate the motor 9 and rotate the screws 4 in adirection (clockwise as seen in FIG. 3) to move the ram upwardly. As theram approaches the end of its stroke the doors l7 automatically open, aspreviously described, and the waste falls into the container 3. At theend of its upward stroke the ram 2 actuates a microswitch 31 at the topof the compactor to reverse the motor 9 and start the ram on itsdownward stroke. The ram doors 17 then close automatically, aspreviously described. The ram moves into the container 3 and compactsthe waste in the container until a predetermined force, for example 2tons, is reached at which time a load sensing device 32 (to behereinafter described) associated with the drive belt 13 operates amicro-switch 33 to stop the motor. On stopping of the motor the rampressure is released slightly owing to any lost motion in the drivemechanism and the natural resilience of the parts of the mechanism. Thusthe ram is disposed within the container in the inoperative position.

The load sensing device 32 (shown clearly in FIG. comprises a lever 34pivoted at its outer end to a fixed pivot pin 35 and carrying at itsinner end a roller 36 which is held in engagement with a run 37 of thedrive belt 13 by a tension spring 38 connected between the inner end ofthe lever 34 and a mounting hook 39 which is adjustably connected to afixed bracket of the compactor frame 1. When the ram is movingdownwardly, the motor pulley 11 and screw pulley 12 are rotatinganti-clockwise as seen in FIg. 3 so that the run 37 of the belt 13 isunder tension. In operation, as the load is applied to the waste by theram. rotation of the drive screw 4 and thus pulley 12 is slowed downwhile the motor pulley 11 is tending to rotate at its normal operatingspeed. Thus the tension in the run 37 of the belt 13 increases and theroller 36 and lever 34 are moved against the force of the spring 38.Upon a predetermined movement of the lever 34, it actuates themicroswitch 33 to switch off the motor 9. The spring force of spring 34required to allow a desired maximum ram force can, of course, becalculated.

A micro-switch 41 which controls a warning lamp 40 is provided which, innormal downward movement of the ram, is actuated thereby to prevent thelamp 40 being switched on. If, however, the ram does not move asufficient distance downwardly to actuate the microswitch 41, Le. whenthe container 3 is full of waste, then when the predetermined load isreached and the motor 9 is switched off. the micro-switch 41 actuatesthe warning lamp to show that the container is full.

To empty the waste, an unload button 42 is actuated to operate the motorand cause the ram to move upwardly out of the container. When the ram 2is raised the motor 9 is automatically switched off and the container 3can be removed from the compactor. The container has wheels 43 to permiteasy removal from the compactor and easy conveyance to a wastecollection point. Preferably the container is lined with a bag forexample of polythene, which can be removed and tied so that the waste isin an easily disposable form. After removal of the waste a fresh bag isinserted in the container which is replaced in the compactor. Amicroswitch 44 is provided inside the compactor on the wall remote fromthe opening from the container, which is actuated when the container isfully inserted in the compactor. The micro-switch 44 controls theelectrical power supply such that if the container is not in place inthe compactor the ram will not operate.

As can be clearly seen in FIG. 6, rubber blocks 45 are mounted betweenrespective wheels 43 and the container 3, the blocks 45 beingincompressible until a predetermined load, say lbs, which is greaterthan the weight of a fully laden container, is applied thereto. When aload greater than 80 lbs is applied, i.e. when the ram is exerting aload, the blocks 45 are compressed and the container drops on to a fixedsupport member 46 which is connected to and supported by mild steelpacking blocks 47 on the compactor frame. Thus when the ram is notexerting a load the weight of the container and waste is taken by thewheels 43 and the container is just clear of the support member 46 sothat the container can easily be moved into and out of the compactor,and when the ram exerts a load it is transferred to the compactor framethrough the packing blocks 47.

FIGS. 7 and 8 illustrate an alternative form of dooroperating mechanismwhich is located adjacent the hinged edge of its associated ram and atthe back of the ram instead of at the side of the ram centrally of eachof the doors as in the above-described embodiment. The mechanism has arod 19a supported in upper and lower guide members 20a attached to theframe of the ram 2. A coil compression spring 24a acts between the lowerguide member 20a and an abutment member 25a secured to the rod 19a by apin 26a. The rod 19a is connected at its lower end to a slide member 51extending through and guided in a slot 52 in one side of the ram 2, theslide member 51 having a pivotal connection with the upper end ofa link22a, the lower end of which is pivotally connected to a lug 53 welded tothe door 17a which is mounted on a pivot shaft 23 for rotation about theshaft axis. The link and slot 52 are enclosed by a cover 55 to preventwaste clogging the mechanism, the cover preferably extending the lengthof the ram so that there are no shelves on which waste can collect.

Operation of the door-operating mechanism is generally similar to thatpreviously described. Briefly, near the end of the upward ram stroke therod 19a engages a fixed frame memberand moves downwardly relative to theram against the bias of spring 24a, the slide member 51 movingdownwardly in the slot 52 with link 22a to pivot the doors 17a abouttheir shafts 23 anti-clockwise and clockwise, respectively, as seen inFIG. 7. Downward movement of the ram effects closure of the doors.

FIGS. 9 and 10 show a modification which permits the ram-operatedmicro-switches and the associated electrical apparatus to bedisposedremote from the working area of the ram, in this instance above the ram.A slave screw 61 is drivingly coupled to the drive feed screws bynonrotatably mounting the slave screw on the pulley 5 of one of thedrive feed screws 4. The slave screw carries a nut member 62 having alongitudinal slot 63 (FIG. which receives an edge of a fixed plate 64supporting micro-switches 65, 66, 67. Movement of the nut along theslave screw corresponds to and represents movement of the ram in itsfeed screws 4', but on a reduced scale. The scale reduction in this caseis achieved by providing the slave screw 61 with a lead less than thelead of the feed screws 4, the ratioof the leads determining the ratioof the movements of the nut member 62 and the ram 2. The scale reductioncould be achieved in some other way, for example by introducingreduction gearing between the drive feed screws 4 and the slave screw61. v

Thus, when the ram 2 moves through its cycle, the nut member 62 movescorrespondingly along the slave screw and operates the micro-switches65-67. The upper micro-switch 65 corresponds to the switch 31 previouslydescribed and is actuated at the end of the upward stroke to reverse themotor 9 and the microswitch 66 corresponds to the previously describedswitch 41 to indicate when the container is full. The lower switch 67 isoperated when the ram reaches the end of its downward stroke.

It will be appreciated that the switches 65-67 can be smaller and lessrobustthan their counterparts in the previously described embodiment andare therefore cheaper. Furthermore, the micro-switches and all theirelectrical connections are away from the working area of the ram toreduce any risk of accident or damage and to make servicing or repair ofthe electrical system much easier and reduce problems of insulation. Themotor 9 is conveniently also mounted above the ram working area, so thatall the electrical connections are clear of the ram working area, whichmay be washed out or hosed down without damaging the electricalcircuitry. However, it will be appreciated that the motor can be mountedin any desired position with suitable modification to the drivetransmission.

FIG. 11 illustrates a modification to the door 16. The modified doorcarries at its lower end two rollers 71, one on each side, movable alongrespective fixed guide tracks 72 extending inwardly and downwardly. Alink 73 is pivotally connected at one end to the door 16 at a point 74intermediate the upper and lower ends of the door and at the other endat 75 to a fixed member 76. The door 16 is shown in its closed positionin full lines and is opened by pulling a handle at the upper end of thedoor so that the rollers slide along their guides, the pivot points 74travelling through an arc of a circle whose centre is pivot point 75,until the door is in its partially open position shown in chain dottedlines. Further pulling of the handle moves the door to its fully openposition shown in chain dotted lines in which the door acts also as achute for waste material fed into the opening. The extent to which thisdoor moves out from the compactor during opening is limited by thelength of the link 73 and is less than that of the previously describeddoor. With this modification the user does not have to move backwards toavoid the door when opening it.

It will be appreciated that the use of three drive screws ensures that asubstantially even load is applied to the waste across the whole area ofthe ram.

It will be apparent to those skilled in the art that modifications ofthe above described waste compactor are possible within the scope of theinvention. For example, the mechanism 18 for controlling the ram doorsmay be disposed with. The doors may be freely hinged to open under theaction of gravity and to close when 6 they come in contact with thewaste in the container on the downward stroke of the ram. The doorswould then preferably be suitably shaped to avoid digging into the wasteon the downward stroke.

Further, a different load sensing device could be used instead of theabove described device.

I claim:

l. A waste compactor for compacting waste material in a container,comprising a housing; a waste-receiving container located within thehousing and being removable therefrom; a ram mounted for reciprocalmovement within the housing and cooperating with the con tainer tocompact waste material emptied into the compactor into said container;drive means for reciprocating the ram between a retracted position and acompressed position where it compresses waste material into thecontainer, said ram having an opening therethrough; closure means forclosing said ram opening; and control means for opening said closuremenas when the ram moves in a direction toward its retracted positionand for closing said closure means when the ram moves in a directiontoward its compressed position, said control means keeping the ram inits compressed position against previously compressed waste whileadditional waste material is being emptied into the compactor at a levelabove said ram and upon selective actuation reciprocating said ramtoward its retracted position to open the closure means and permit thecollected waste material to pass through said opening into saidcontainer and to thereafter reverse the direction of the ram to compressthe wasted material that has passed through the ram into said containerand to again hold the compressed waste in compression while additionalwaste is emptied into the compactor.

2. A waste compactor according to claim 1 wherein said closure meanscomprises at least one door pivotally attached to said ram, and saidcontrol means comprises at least one door-operating means operative toopen the door automatically as said ram approaches its retractedposition and to close the door automatically during its compressionstroke.

3. A waste compactor according to claim 2, wherein said door-operatingmeans comprises an operating rod movable with said ram, a linkagepivotally connecting said associated door to said operating rod, and astop engageable by said rod towards the end of said upward stroke ofsaid ram to permit movement of said ram relative to said operating rodand effect pivotal movement of said door to open it.

4. A waste compactor according to claim 1, wherein said drive meanscomprises a plurality of spaced-apart parallel drive feed screwsrotatably mounted in said compactor, ram frame members supportedrespectively by said drive feed screws, and movable therealong, drivetransmitting means, and a drive motor drivingly coupled through saiddrive transmitting means to said drive feed screws.

5. A waste compactor according to claim 4, wherein said drivetransmitting means comprises a toothed belt and pulley system.

6. A waste compactor according to claim 5, wherein said belt and pulleysystem comprises two pulleys, one connected to said drive motor and theother to one of said drive feed screws, and a drive belt extendingaround said pulleys to transfer the drive from said motor to said drivefeed screw, and further comprising load sensing means for sensing apredetermined load of said ram on said waste material, said load sensingmeans comprising a lever mounted for pivotal movement about a fixedaxis, roller means carried by said lever, spring means biassing saidroller into engagement with one run of said drive belt and switch meansoperable by said lever, said lever being movable towards said switchagainst said bias of said spring means as the tension in said belt runincreases due to said ram compacting said waste material, whereby saidswitch is actuated when said lever moves through a predetermineddistance corresponding to said predetermined load.

7. A waste compactor according to claim 4, further comprising ramposition indicating means including a further feed screw rotatablymounted remote from said ram and drivingly coupled to said drive feedscrews, a nut member carried by said further feed screw and movabletherealong, movement of said nut member along said further feed screwrepresenting on a reduced scale movements of said ram along said drivefeed screws, and at least one switch means mounted for engagement bysaid nut member to control said drive motor.

8. A waste compactor according to claim I, wherein said drive meansreciprocates said ram to a compressed position near the bottom of saidcontainer and to a retracted position outside of said container.

9. A waste compactor for compacting waste material in 'a container,comprising a ram, drive means operable to reciprocate 'said ram into andout of said container to compress the waste material thereinQand ramposition indicating means located remote from said ram, and comprising afeed screw mounted for rotation, a nut member carried by said feed screwand means holding said nut member against rotation'said feed screw beingcoupled to said drive means whereby movement of said nut member alongsaid feed screw represents on a reduced scale movement of said ram inresponse to operation of said drive means.

1. A waste compactor for compacting waste material in a container,comprising a housing; a waste-receiving container located within thehousing and being removable therefrom; a ram mounted for reciprocalmovement within the housing and cooperating with the container tocompact waste material emptied into the compactor into said container;drive means for reciprocating the ram between a retracted position and acompressed position where it compresses waste material into thecontainer, said ram having an opening therethrough; closure means forclosing said ram opening; and control means for opening said closuremenas when the ram moves in a direction toward its retracted positionand for closing said closure means when the ram moves in a directiontoward its compressed position, said control means keeping the ram inits compressed position against previously compressed waste whileadditional waste material is being emptied into the compactor at a levelabove said ram and upon selective actuation reciprocating said ramtoward its retracted position to open the closure means and permit thecollected waste material to pass through said opening into saidcontainer and to thereafter reverse the direction of the ram to compressthe wasted material that has passed through the ram into said containerand to again hold the compressed waste in compression while additionalwaste is emptied into the compactor.
 2. A waste compactor according toclaim 1 wherein said Closure means comprises at least one door pivotallyattached to said ram, and said control means comprises at least onedoor-operating means operative to open the door automatically as saidram approaches its retracted position and to close the doorautomatically during its compression stroke.
 3. A waste compactoraccording to claim 2, wherein said door-operating means comprises anoperating rod movable with said ram, a linkage pivotally connecting saidassociated door to said operating rod, and a stop engageable by said rodtowards the end of said upward stroke of said ram to permit movement ofsaid ram relative to said operating rod and effect pivotal movement ofsaid door to open it.
 4. A waste compactor according to claim 1, whereinsaid drive means comprises a plurality of spaced-apart parallel drivefeed screws rotatably mounted in said compactor, ram frame memberssupported respectively by said drive feed screws, and movabletherealong, drive transmitting means, and a drive motor drivinglycoupled through said drive transmitting means to said drive feed screws.5. A waste compactor according to claim 4, wherein said drivetransmitting means comprises a toothed belt and pulley system.
 6. Awaste compactor according to claim 5, wherein said belt and pulleysystem comprises two pulleys, one connected to said drive motor and theother to one of said drive feed screws, and a drive belt extendingaround said pulleys to transfer the drive from said motor to said drivefeed screw, and further comprising load sensing means for sensing apredetermined load of said ram on said waste material, said load sensingmeans comprising a lever mounted for pivotal movement about a fixedaxis, roller means carried by said lever, spring means biassing saidroller into engagement with one run of said drive belt and switch meansoperable by said lever, said lever being movable towards said switchagainst said bias of said spring means as the tension in said belt runincreases due to said ram compacting said waste material, whereby saidswitch is actuated when said lever moves through a predetermineddistance corresponding to said predetermined load.
 7. A waste compactoraccording to claim 4, further comprising ram position indicating meansincluding a further feed screw rotatably mounted remote from said ramand drivingly coupled to said drive feed screws, a nut member carried bysaid further feed screw and movable therealong, movement of said nutmember along said further feed screw representing on a reduced scalemovements of said ram along said drive feed screws, and at least oneswitch means mounted for engagement by said nut member to control saiddrive motor.
 8. A waste compactor according to claim 1, wherein saiddrive means reciprocates said ram to a compressed position near thebottom of said container and to a retracted position outside of saidcontainer.
 9. A waste compactor for compacting waste material in acontainer, comprising a ram, drive means operable to reciprocate saidram into and out of said container to compress the waste materialtherein, and ram position indicating means located remote from said ram,and comprising a feed screw mounted for rotation, a nut member carriedby said feed screw and means holding said nut member against rotationsaid feed screw being coupled to said drive means whereby movement ofsaid nut member along said feed screw represents on a reduced scalemovement of said ram in response to operation of said drive means.